I had a dual boot PC running Ubuntu 12.04 and Windows 7. About a month back, I deleted the Ubuntu partition via the disk management utility (I do not remember whether or not I formatted the partition after performing this action).

I ran into some grub issues and used lilo to solve the issue. I followed the simple instructions described in this blog post.

I now realize that there were some files in the Ubuntu installation that I need. Of course, I backed up the data, but not this folder apparently. Is there any way to get the data back?

I tried following the process suggested on another post on askubuntu (suggesting the use of TestDisk), but was not able to even install TestDisk. The live USB I use is running Ubuntu 12.04 and it does not have a synaptic package manager. Installing from the terminal does not work because even after I type:

sudo apt-get update
sudo apt-get upgrade

the command:

sudo apt-get install testdisk 

fails to work.